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Best EPs for a XT10i?

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#1 TahoeNoob

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Posted 24 November 2012 - 11:06 PM

Hello friendly experts!

Next week I'll be receiving a used XT10i. :jump: It's going to be delivered by a friend who lives out of the area. I bought the scope on Craigslist, my friend is just the delivery man. Along with the scope, I'll get two eyepieces; the ones that originally came with the scope:

1) 25mm/1.25" Sirius Plossl
2) 10mm/1.25" Sirius Plosel

I will not be receiving a barlow.

So, my question is... should I sit tight and see how things go, or should I buy a couple eyepieces along with a barlow? If I buy something, I don't want to buy rock bottom stuff, but I can't afford high end stuff. What are some good mid-range eyepieces and barlows that're compatible with a XT10i? Do I need any 2 inch EPs, and how much can I expect to pay for what I need?

I saw one person recommending Explore Scientific 82* EPs. Bang for the buck wise, are they a good deal?

I hope to use this scope mostly for viewing DSOs, and my skies are pretty darn dark! There's some light spill-over from a nearby town, but not too much. (I think most people would be very happy to be in my situation.) Do I need any filters? :)

#2 TahoeNoob

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Posted 24 November 2012 - 11:21 PM

I should add that I'm a little bit concerned, because I read that XT10s are "hard on EPs."

#3 GOLGO13

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Posted 25 November 2012 - 12:00 AM

The ES eyepieces would be your best choice. Especially if you don't want to spend too much money. I really like the 6.7mm 82 degree myself (mine isn't ES, but it's pretty much the same eyepiece...the 6.7mm Meade UWA 5000 appear to be made by the same folks or copies).

Since those are on sale right now you may want to get one or two. The best part is the wide field of view allows you to observe longer before nudging the scope. But if you go too cheap on wide field eyepieces, their flaws can be exposed by the fast scope.

2 inch eyepieces are not required. I use a 24mm 68 degree as my low power which is still 1.25. But 2 inch low powers can be nice. Just don't go too cheap on those with that scope.

#4 GOLGO13

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Posted 25 November 2012 - 12:04 AM

For filters you may want to get an Oxygen III for objects like the Veil Nebula. Use it with lower power. But if you are in dark skies like that you should probably try a bit without. Check out Globular clusters...and for certain the Wild Duck Cluster :) ...The Orion Nebula goes without saying.

The Intelliscope has a monthly tour which is worth using. Just do a month or two plus or minus from the current month.

ENJOY :)

#5 timfiskwa

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Posted 25 November 2012 - 12:06 AM

Hello TahoeNoob and welcome to cloudynights. I highly recommend a 2x Barlow like the Orion shorty to get good planetary closeups. I also would get a 7.5 or 6.3 mm to power up in good seeing, useful for close double stars, lunar, and planets. The 25mm is a good low power eyepiece. Great for star hopping. Maybe a 17mm or 12.5 mm for midrange, all Plossls. I am thinking of a 2" for myself, perhaps in the 25-32mm range. Premium eyepieces really are nice and the views are great if you can get them like the panoptics or ES 32mm, but they are beyond my budget.

#6 frito

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Posted 25 November 2012 - 02:19 AM

Hello TahoeNoob and welcome to cloudynights. I highly recommend a 2x Barlow like the Orion shorty to get good planetary closeups. I also would get a 7.5 or 6.3 mm to power up in good seeing, useful for close double stars, lunar, and planets. The 25mm is a good low power eyepiece. Great for star hopping. Maybe a 17mm or 12.5 mm for midrange, all Plossls. I am thinking of a 2" for myself, perhaps in the 25-32mm range. Premium eyepieces really are nice and the views are great if you can get them like the panoptics or ES 32mm, but they are beyond my budget.


I agree. fancy wide fields are great to have but are not a necessity. i personally bought the 5 pc orion plossl set to get myself started and give me options. it helps that they purposefully forgo an EP around 25mm because thats the one they put with the majority of their new scopes. the set comes with a 6.3, 7.5, 10, 17, and a 42mm (42 deg on the 42) along with the shorty 2x barlow and your basic run of the mill color filters and a .9 neutral density filter in a decent case that has some room to stick some more things in. at 150-170 bucks its hard to beat to get one started with some decent eyepieces.

i will say that out of the various eyepieces i use the 6.3, 10, 17 and 42 the most. having all those high power options at hand is very nice for viewing planets because if the seeing isn't quite good enough you can just swap to a slightly lower power and get more detail.

the 42mm sounds like it would be a great low power and it is but because its 1-1/4" and only has a 42 deg AFOV its true field is only a little bit better than the 25mm that comes with the scope but none the less is easier to use and because the top lens is recessed quite a bit in the housing its a good general view EP that is very resistant to dewing up. it made my 25mm obsolete until i picked up an O-III filter and i found that for whatever reason the 42 seems to cause some crazy reflections in the upper housing when using that filter so my 25mm gets dedicated O-III use when i'm viewing those types of nebula now so its regained some of its usefulness again.

before buying more expensive EP's i'd go out to star party's at a local club if you can and use/borrow other folk's units. i've viewed through quite a few high end wide field EP's and a number of lower end ones as well. the time i got to view through some Televue's it was in an 18" obsession so its kind of hard to tell how much was the EP and how much was the scope but the views were breathtaking for sure. just yesterday i got to use someones Orion Q70 38mm in both his XT10 as well as my XT8 and i have decided that is my next and first 2" EP. i spent more time with it in my 8 as thats what i'm going to use it on but the views were very good in both scopes in my opinion and thats good enough for me. i'm personally going to save my cash to get a bigger scope next because from what i've seen that makes the biggest difference in what you can and do see along with viewing conditions (light pollution, transparency, seeing etc.)

another thing thats much cheaper than opting for expensive wide fields on these dobs that will help tremendously with viewing planets and double stars at high power is upgrading the alt and az bearing surfaces. 2 days ago i bought a sheet of Fiber Reinforced Plastic (FRP) and cut a diameter for the base bearings to ride on and 2 strips that i tied up to the alt bearings like another member on here Jason did on his scope and it made the alt so smooth i had to make and strap a counter weight to the back of my scope. i've got more end weight than you right now though as i added a Rigel and a 8x50 RACI finder to my XT8 without the RACI it does not need the counter weight even with a pretty heavy EP. the advantage in doing this though is that when tracking planets before at high power i'd be constantly messing with the position to get say jupiter at the top of the field so i can then let the scope settle then view it for 5 seconds or whatever then do it all over again. with the FRP bearing mod i no longer overshoot moving the scope at high power and it takes much much less time for it to settle down after moving it. this is much less of an issue at low power but its still somewhat of an issue.

#7 kfiscus

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Posted 25 November 2012 - 02:58 AM

Lots of people rave about ES eps. I've not tried any. I opted for buying used Televues from highly-rated Amarters and CNers. I haven't regretted it for a minute. 35 Pan, 24 Pan, 13 T6, 7 T6.

#8 CosmoSat

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Posted 25 November 2012 - 04:43 AM

For planetary I would suggest this 5mm 1.25" Paradigm Dual ED eyepiecefor ur f/5 scope.

The 2X apochromatic ED Barlow.. Done know if it can be converted to work as a 1.5x too tho.

Or u can consider this GSO 1.25" 2x Achromatic Barlow Lens if u want the 1.5x option.

A 15mm or so wide angle eyepiece for Deep sky observing.. like the 14mm ES 82° eyepiece(getting mixed reviews this one).

Clear Skies!

#9 rick-SeMI

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Posted 25 November 2012 - 08:22 AM

When I bought my Orion 90mm Mak-Cass I also purchased the Orion eyepiece case with 5 eyepieces, 5 color filters, a neutral density filter and a shorty 2x barlow.

Well I used the eyepieces (plossls) a little over a year and used one or two of the filters a couple of times.

My next purchase was the Orion Q70 26mm 2".
Then the ES68° 24mm, ES82° 14mm and ES82° 6.7mm 1.25" EP's.
In close succession an Orion Ultrablock filter, DGM NPB filter and a Lumicon OIII filter.

These are the eyepieces I use the most with the XT10i:
ES 82° 14mm and ES 82° 6.7mm.
I also use the Ultrablock, NPB, OIII and Orion Neutral Density (from the case) and the 2x barlow on occassion.

#10 Achernar

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Posted 25 November 2012 - 09:28 AM

With F/5 and faster telescopes, you really cannot get good views with many low end eyepieces. A good Plossl will work, but they have a narrow field of view compared to more modern eyepieces. Inexpensive wide field eyepieces often do not fare well at F/5 or below. They are just not corrected well enough for astigmatism and other aberrations for short focal ratio telescope. The Explore Scientific eyepieces are moderately priced and they do work very well at F/4.5. I have all of them except the 30mm model, they are very sharp and very contrasty. Field flatness is good and lateral color around the edge is there but not enough to be a concern. There is some distortion, which is common in many ultra-wide angle eyepieces, but unless you are looking at the sun or moon, it's not going to be apparent. They do have a little flaring issue when there is a very bright object just outside the field of view, mainly with the 8.8mm but that is maninly with the moon. Fit and finish are excellent They come pretty darn close from what I can see to Naglers but at a much lower price. There is one caveat however, if you wear glasses, you will have to take them off to look through these eyepieces, or wear contacts. I wear glasses and consider taking them off an acceptable tradeoff for all the advantages the ES 82 degree eyepieces offer. You may or may not be able to look through them without eyeglasses on. Where these eyepieces excell are deep sky objects, and the huge 82 degree apprent field of view makes finding, and tracking objects a lot easier. In general, they are a good choice for a F/4.5 or F/4.7 Dob of any aperture. They are all very good, but from what I can see, the 24mm, 11mm and 6.7mm are a little better than the others. You do not need 2-inch eyepieces unless you are looking for a low-power, wide or ultrawide angle eyepiece. In any case, the telescope is already able to accomodate them since a 10-inch Dob usually has a 2-inch focuser. ES also has a line of really good 68 degree eyepieces as well that deserve consideration. There are other 68 degree eyepieces that have good performance with long eye-relief, which will allow you to see the whole FOV with your glasses on.

Taras

#11 City Kid

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Posted 25 November 2012 - 10:35 AM

I've had an XT10 for 10 years or so and I can tell you what focal length eyepieces I've found to be the most useful with that scope. For me, the mid-range eyepieces get the most use. Something in the 17mm - 13mm range. For my taste the eyepieces in that range provide the most pleasing views on most DSOs. In the higher power range, eyepieces from 6mm to 8mm have been the most useful. Again this is for my tastes and my situation.

I think you can do just fine using the eyepieces that come with the scope for awhile. The 25mm will allow you to find objects and will frame most of the larger objects quite well. The 10mm will give you good upper mid-range magnification. Time spent using those will give you an idea of where you want to go from there.

#12 TahoeNoob

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Posted 25 November 2012 - 11:27 AM

How would it be if I went with something like this:

1) BUY- 28mm/2" ES 68*
2) HAVE 25mm/1.25" Sirius Plossl
3) SKIP 18mm/2" ES 82*
4) HAVE 10mm/1.25" Sirius Plosel
5) BUY- 6.7mm/1.25" ES 82*

6) BUY- 2X apochromatic ED Barlow for 2" eyepieces, with 1.25" adapter This is the barlow that CosmoSat recommended. (Another barlow option would be to buy the other barlow that CosmoSat recommended, the 2x/1.5x one. That option would fill the 18mm void. Would that be a better option????)

If the 18mm eyepiece was 1.25 I'd probably buy that too. It's 2" though.

BTW, the focuser on this XT10i, that I'm getting, is going to be a 2" Crayford 2 speed focuser from Scope Stuff (with 1.25 adapter)... it was upgraded. I'm not sure if that matters, or not.

#13 City Kid

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Posted 25 November 2012 - 11:50 AM

I think that would give you a good range of magnifications.

#14 csrlice12

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Posted 25 November 2012 - 11:59 AM

While heavy, The ES82, 24mm (2") is a heavy beast, the 10XTi can more then handle it. Next I'd get the ES82 11mm as it is the best of the bunch. Next is a tossup between getting the 8.8mm or a barlow for the 11mm. Me personally, my barlows exist to take up space in my bag; but they were useful until I no longer needed them, and do work well (get the shorty barlows, any of the GSO clones will do.

The ES82 24mm will give you 50X with right at 5mm exit pupil, which is considered near perfect. I'm attaching a chart showing how the different f/l ES82* (and some ES68*) would work in the 10XTi. If the weight of the 82* 24mm, consider the ES68* 24mm as it is much lighter and a little cheaper, but also works well in the 10XTi.

Another item to invest in is a collimation system, the cap that comes with the scope is only used to check the primary alignment. You will need a good cheshire/collimating eyepiece. You can get good results with these tools, however a laser collimating system will be more accurate, but also more expensive. The Howie Glatter laser/Tublug for reflectors is considered the best on the market as it is the only laser I kow of on the market that WON'T lose it's own collimation (do you really want to collimate your collimater?). You'll also want to find something comfortable to set on. I've used an old milk crate for a long time; am considering that drummers chair from Harbour Freight at $20.

I have to say, the 10mm is my alignment eyepiece to line up the finderscope and do the 2-Star alignment. If it's in view of the eyepiece then (anywhere in the field), it'll be in the FOV of the wide-fields. Other then that, the 10mm is a paperweight. The 25mm Plossel is a very good plossel, but has a limited FOV.

Also, there are a lot of free apps for your computer/phone/tablet like Stellarium to help you learn the skies.

You're gonna love that scope. Clear Skies.

#15 TahoeNoob

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Posted 25 November 2012 - 12:58 PM

Thanks! This is the type of thread I was hoping for! :)

>> I'm attaching a chart showing how the different f/l ES82* (and some ES68*) would work in the 10XTi.

There's an attachment? I'm not seeing one.

#16 panhard

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Posted 25 November 2012 - 01:04 PM

Me neither.

#17 csrlice12

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Posted 25 November 2012 - 01:23 PM

ooops, here tis.

Attached Files



#18 TahoeNoob

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Posted 25 November 2012 - 01:26 PM

Ok, now I'm completely confused!

The Tublug, itself, doesn't seem to be a self contained laser emitting device, as the Orion Deluxe Collimator is. Do you have to buy a separate laser unit that fits inside the Tublug?

I think this line, here, is what's confusing me: "Use with a regular laser collimator in single beam mode to perform barlowed laser Newtonian primary mirror alignment on closed tube reflectors."

Use with a regular laser collimator? Huh? You're supposed to stick an Orion Deluxe Collimator into the Tublug? Is that what they're saying? I think I'm missing something.

The quote is from this site:
http://www.greatreds.../collimator.htm

#19 csrlice12

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Posted 25 November 2012 - 01:34 PM

Yes, the laser is separate from the Tublug. This is a complete collimating system for both the primary and secondary mirrors. You'll never need another. A 2" Glatter laser and Tublug runs about $265. Like I said, you could go the Cheshire/collimation eyepiece route and get pretty good results for cheaper.

#20 TahoeNoob

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Posted 25 November 2012 - 01:56 PM

Oy! LOL

Is this the "Barlowed Laser Collimation" method that I've read about:

http://www.cameracon...collimation.pdf

Why not just use a regular Barlow Lens and an Orion Deluxe Collimator?

I don't mean to be dense... but still am. I'm sorry; I'm 100 percent sure that I'm missing something. :crazy:

#21 WAVT

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Posted 25 November 2012 - 02:04 PM

You have chosen a great scope! The 10" push-to Dob is a favorite for lots of folks. Good luck with it.

The 11mm ES 82° eyepiece is a great one, and priced well. It will blow the socks off the 10mm plossl that comes with those scopes. It also barlows very well. I like the the GSO 2X 1.25" barlow as you can unscrew the lens and make it a 1.5X barlow as well. The 11mm ES 82° and a barlow will really give you some very good moderately high power viewing options.

Depending on your budget, I would also recommend a low power wide field eyepiece. In a 1-1/4" size, you can't do any better than a 32mm Plossl (for the money) Sterling, GSO 32mm Plossls are decent. The TV 32mm Plossl is excellent.

Moving up and out to a 2" low power, wide field eyepiece will enable you to take in some wonderful large patches of sky and really put objects in context with their surroundings. The 10" dob has good wide field capabilities that you should take advantage of.

The TV 31mm Nagler coupled with a Paracorr is the gold standard for gorgeous wide field views in your scope, but... the cost is astronomical.

There is an aboration called coma that is inherant in your scope. Cheap low power eyepieces do a *BLEEP* job of correcting for it and you will see seagulls instead of stars, especially around the perifery of view. TV Naglers and some of the ES eyepieces do a better job correcting for coma, and the paracorr all but eliminates it. Most people are so stunned by the wide field views that they don't notice or object to the coma they see when looking thru a good quality low power eyepiece, and for them a paracorr is not a necessity.

The 30mm ES° eyepiece strikes a good balance between price and quality. For around $250 you will get huge enjoyment cruizing the milky way and it will take in Pleiades nicely.

I bought a 38mm Orion Q70 clone(an Agena 38mm SWA) and use it in my 10 dob and really like it. Of this inexpensive line of 70° eyepieces, the 38mm is the best of the lot. Yes, the exit pupil is wasteful, and the stars have tails in the outer 1/3 of view but I still keep going back to it every time I have my 10" dob out. I bought it used on CN classifieds for $60. I would suggest you keep yours eyes open for a similar deal. You just might get hooked on big wide fields and end up investing in premium optics. You will always be able to sell it if it doesn't float your boat.

Good luck with your new scope.

#22 JohnMurphyRN

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Posted 25 November 2012 - 02:18 PM

Depending on your budget, I would also recommend a low power wide field eyepiece.

Moving up and out to a 2" low power, wide field eyepiece will enable you to take in some wonderful large patches of sky and really put objects in context with their surroundings. The 10" dob has good wide field capabilities that you should take advantage of.

The TV 31mm Nagler coupled with a Paracorr is the gold standard for gorgeous wide field views in your scope, but...


The 30mm ES° eyepiece strikes a good balance between price and quality. For around $250 you will get huge enjoyment ...


I concur...

There's an ES 82* 30mm in the EP classifieds for $200 (not mine).

#23 TahoeNoob

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Posted 25 November 2012 - 02:31 PM

I think I'm starting to get a handle on this. Tremendously useful information here!

Thank you everybody!

#24 Warren914

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Posted 25 November 2012 - 02:50 PM

The Baader Hyperion 8-24mm zoom with 2x ED Barlow would give you a wide range of focal lengths down to 4mm, in either 1-1/4 or 2-inch format.

I use mine in 2-inch format with a GSO ED barlow. I find it is easier to turn the knob to find optimum magnification rather than fumble through multiple eyepieces.

#25 panhard

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Posted 25 November 2012 - 03:00 PM

I use my 8mm & 13mm Hyperions the most. I must also mention that I also have the fine tuning rings.






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